Cytogenetic analysis of HER1/EGFR, HER2, HER3 and HER4 in 278 breast cancer patients

Breast Cancer Research

Table 4 Results of fluorescence in situ hybridisation (HER2) and immunohistochemical staining (HER1–HER4)

	FISH	Immunohistochemistry
	HER2	HER1	HER2	HER3	HER4
Evaluation characteristics	n = 231	n = 178	n = 214	n = 173	n = 191
0	n.r.	152 (85.4)	112 (52.4)	43 (24.9)	120 (62.8)
1+	n.r.	7 (3.9)	54 (25.2)	115 (66.5)	49 (25.7)
2+	n.r.	11 (6.2)	26 (12.1)	14 (8.1)	17 (8.9)
3+	n.r.	8 (4.5)	22 (10.3)	1 0.5)	5 (2.6)
Positive	46 (19.9)	26 (14.5)	48 (22.4)	130 (75.1)	71 (37.2)
Negative	185 (80.1)	152 (85.5)	166 (77.6)	43 (24.9)	120 (62.8)

Numbers in parentheses are percentages. The total sample size was n = 278. Results in bold define data considered positive for immunohistochemistry. FISH, fluorescence in situ hybridisation; n.r. = non-relevant for FISH; cut-off point for HER2 FISH analysis (≤1.5 vs. ≥1.6) distinguishes amplified (positive) or normal (negative) gene status.

ISSN: 1465-542X